Sonic and his friends find themselves in serious trouble. Their new enemy is Metal Sonic, created by Dr. Robotnik. The villain is aided by the mysterious hedgehog Shadow. While Tails and Knuckles are occupied with a race, the main hero ends up in the center of New York City, where an army of clones awaits him. Amy Rose arrives just in time to help. Armed with a massive hammer, she is ready to crush any enemy. Now their opponents are in real trouble.